With the recent advances in Internet content distribution, including peer-to-peer networks and real-time video streaming systems, in order to deter unauthorized distribution of content, it data can be embedded in video to trace intercepted potentially illegally distributed video back to a point of distribution. The point of distribution is often an authorized viewer, such as a cinema where pirated copies are made with camcorders, or a television integrated receiver decoder (IRD) whose output is captured and re-encoded into a video file. After tracing the source, measures can be taken to prevent further unauthorized distribution.
Embedding signals in video is a field rich in both academic research and commercial inventions. Covert watermarking, i.e. embedding an imperceptible yet visible watermark in the video, is well known in the art, as are overt watermarks that are clearly visible and overlaid/displayed on top of the video. Steganographic watermarks are also well known in the art.